9H4H

trans-aconitate decarboxylase Tad1_S320A

9H4H の概要

• エントリーDOI: 10.2210/pdb9h4h/pdb
• 分子名称: Trans-aconitate decarboxylase 1 (2 entities in total)
• 機能のキーワード: decarboxylase, biosynthetic protein
• 由来する生物種: Mycosarcoma maydis (Corn smut fungus)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 107966.86

構造登録者

Zheng, L.,Bange, G. (登録日: 2024-10-18, 公開日: 2025-03-19)

主引用文献

Zheng, L.,Li, W.,Christ, M.,Paczia, N.,Buckel, W.,Mais, C.N.,Bolker, M.,Freitag, J.,Bange, G.
Mechanistic and structural insights into the itaconate-producing trans -aconitate decarboxylase Tad1.
Pnas Nexus, 4:pgaf059-pgaf059, 2025

PubMed Abstract: Itaconic acid belongs to the high-value precursors for the production of biomass-based industrial compounds. It originates from the tricarboxylic acid cycle, and depending on the organism, it is produced by different biosynthetic routes. The basidiomycete fungus synthesizes itaconic acid via isomerization of -aconitic acid to -aconitic acid, and subsequent decarboxylation catalyzed by the -aconitate decarboxylase Tad1, which belongs to the aspartase/fumarase superfamily. Since no other decarboxylase has been identified within this protein superfamily, Tad1 constitutes a novel type of decarboxylase. Here, we present high-resolution crystal structures of Tad1, which, together with mutational analysis and nuclear magnetic resonance spectroscopy measurements, provide insight into the molecular mechanism of Tad1-dependent decarboxylation. Specifically, our study shows that decarboxylation is favored in acidic conditions, requires protonation as well as migration of a double bond, and coincides with structural rearrangements in the catalytic center. In summary, our study elucidates the molecular mechanism underlying a novel type of enzymatic decarboxylation and provides a starting point for protein engineering aimed at optimizing the efficient production of itaconic acid.

PubMed: 40045995
DOI: 10.1093/pnasnexus/pgaf059

実験手法

X-RAY DIFFRACTION (2.09 Å)